Refrigerating apparatus



Patented Aug. 10, 1926.

UNITED STATES 1,595,426 PATENT OFFICE.

THOMAS B. SLATE, OF NEW YORK, N. Y.,

ASSIGNOR, BY MESNE ASSIGNMENTS Tb' INTERNATIQNAL PATENTS HOLDING CORPORATION, OF NEW YORK, N. Y., ACOR- PORATION OF DELAWARE.

REFRIGERATING APPARATUS.

Original application filed January 10, 1924, Serial No. 685,482. Divided and this application filed September 27, 1924. Serial No. 740,164.

My present invention relates moreparticularly to refrigerating perishable products by means of frozen carbon dioxide entor, and to apply said heat to the frozen carbon dioxide whereby it is absorbed as latent heat, producing a corresponding amount of intensely cold carbon dioxide gas without any intermediate liquid state, said gas being liberated in operative relation to refrigerate such. products, dry them, and protect them from air. Various forms of apparatus working on this principle are set forth in my Patent No. 1,511,306, granted October 14, 1924,,on my application, Serial No. 685,482, filed January 10, 1924 of which this application is a division.

The subject matter of this present application is a heavily insulated package or shipping case filled with perishable products, preferably such as is desired to keep very cold and to preserve from the atmosphere, and particularly such as are not damaged by temperatures far below freezing, as for instance, yeast or ice cream or hard frozen products which are packed in said refrigerator case, in close heated exchange relation with the insulated container of frozen carbon dioxide and the fresh intense- 1y cold gas escaping from said container.

The above and other features of my invention may be more fully understood from the following description in connection with, the accompanying drawings, in which Fig. 1 is a vertical section through a ship ping case containing food products and a carbon dioxide snow chamber or refrigerant container in the center thereof; and

Fig. 2 is a vertical section through the chamber 22.

As shown in these drawings, I provide a simple means using the insulated container 22 for the frozen carbon dioxide within a small shipping box or refrigerator 20 for the shipment of small quantities of perishable products 57 which are thus easily and efficiently refrigerated. By makin snow chamber 22 of the' proper size to displace which forces its way under the lid of c 1amber 22 and continuously keeps the air and moisture displaced.

The container 22 for the frozen carbon dioxide, as also the shipping container 20, may be of balsa wood, but may have the vacuum-wall type of insulation if found desirable. As shown, the covers of both the shipping box and the refrigerant container are close-fitting, and the walls are of exceptional thickness.

As stated in my prior application, carbon dioxide snow as deposited, is light and porous. but I prefer to use it in ice form, made either by highly compressing the snow or by freezing the carbon dioxide directly. As the carbon dioxide ice is nearly twice as dense as water ice and afiords nearly twice as much refrigerant value per pound, it is particularly desirable for shipping purposes where express or freight charges are important.

In this form of my invention where the container or the carbon dioxide is midway of the products to be preserved, it is evident that the insulation cannot prevent freezing of some or all of said product because, regardless of insulation, the fresh gas escaping from the inner container impinges dire-ct quired to reach the relatively l1igh,freezing point of water.

From the above, it will be evident that my present invention differs from all the other forms described in my said prior application and patent in the particular that the carbon dioxide snow or ice refrigerant is in or among packages or masses of the perishable products whereby certain portions of the perishable products are in close proximity to this intense refrigerant, as for instance, portions of packages in contact with the refrigerant container, while other portions are relatively remote, as for in stance, those near or in contact with the dioxide container are ccr hereoi' cdntemplates outer walls of the shipping or storage case. ,Ubviously, the products close to, and particularly those in contact with, the carbon lain to be reduced to temperatures far beloyr parts of the mass that are more remote. "lliis is very different from the situation in all of the other forms shown in my said patent, wherein all of the products are refrigerated by convection currents more than by actual conduction of the heat through portions of the product that are refrigerated.

So far concerns the specific method, my present invention is therefore clearly distinguishable from arrangements of the type shown in Fig. 15 in said patent, wherein there is a refrigerator particularly adapted for precincts requiriln widely different temperatures, but all refrigerated from a single source by convection currents which take efiect lirst on the products that are not damaged by over-freezing and subsequently on other products that are not to be frozen. As contrasted With this, the specific method a box or case in which all of the products to be refrigerated are of the same kind; all of them, even the reinotest, are to be kept near or below freezing; and none of them are damaged by severe over-freezing that will occur in those portions most directly exposed to the refrig'erant.

I claim l. A package for transporting and pie serving masses or parcels of a perishable product of the typenot damaged by severe over-freezing which consists of an outer iiisulated container, in which are packed masses or parcels of such perishable product in close proximity to an insulated inner container enclosing a quantity of frozen carbon dioxide which on absorption of heat through the insulation of said container, passes directly from the solid to the gaseous state; said inner ver-permitting the carbon dioxide gas, as formed, to escape in freezing proximity to said masses or parcels of said. perisl'iable product.

2. A heavily insulated package enclosing in close proximity to a parcel or mass of: material dan'iaged by over-freezing duringshi nnent, a quantity of frozen carbon dioxide insulated from but in freezin relation to said parcel or mass so that portions of the material are more directly and intensely refrigerated than other portions for the purpose and with'the fesult of saidciently reirigrerating more remote portions wnereby on absorption of heat through said insulat on, said carbon dioxide passes directly rein. the solid to the gaseous state;

rid. said as formed escapes in freezing and insulating relation said materials.

3. i trau 1' Jrtation consistinc vented pro ctive casing of insulatin, a

terial enclosing a quantity of frozen carbon dioxide'suliicient to afford refrigeration for the desired period and a quantity of freezable product in freezing proximity to said carbon dioxide'and the gas evaporated therefrom and arranged so that said frozen carbon dioxide is less accessible for exterior heat than said freezable products.

4. A protective casing of insulating ll'itl terial having therein a quantity of frozen carbon dioxide sufficient to afford refrigeration for the desired period and a quantity of freezable product separated from but in freezing proximity to said frozen carbon dioxide and insulated by the gas evaporated therefrom.

5. A protective casing of insulating material having, therein a quantity of frozen carbon dioxide in an insulating container and a quantity of ireezable product in freezing proximity to said frozen carbon dioxide and insulated by the gas evaporated there from.

6. A transportation package consisting of a protective casing of insulating material having packed therein a quantity of frozen carbon dioxide in an insulating container anda quantity of freezable product in freezing proximity to said frozen carbon dioxide and the gas evaporated therefrom, arranged so that said frozen carbon dioxide is less accessible for exterior heat than said freezable products. 7

7. A transportation package consisting of a vented protective easing of insulating inaterial having packed therein a quantity of freczable pro luct in freezing proximity to a quantity of frozen carbon dioxide suflicient to afford the desired amount of refrigeration. a i

8. The combination of a shipping case to be refrigerated a container of frozen -c'arbon dioxide packed in the case with perishable products said container being formed of or including substantial insulating means in contact with said perishable products. the capacity of the container being proportioned to the ,e and contents of the package to -be refrigerated so as to. maintain the products in frozen condition the desired gth of time by the refrigerating, 'pre-- serving and moisture absorbing action of escaping carbon dioxide gas produced by. the evaporation of the frozen carbon dioxide Within the aforesaid container, under normal conditions.

*9. An insulated shipping case, similar parcels of perishable products packed solidly in said case, surrounding and so porting an insulated container of frozen carbon dioxide, hating dimensions corresponding to and fitthugamong the said parcels.

1. An outer thick Walled balsa wood. case or box containing like parcels of perishable an i ier insulated container for frozen carbon dioxide of much smaller size, located Within said outer case and -m direct contact With, and absorbing heat from,

and discharging resultant cold carbon di- 5 oxide among parcels of said perishable products; the capacity of said container and its insulation being proportioned to the amount of refrigeration reqiiired by said product-s.

Signed at New York city in the county of New York, and State of New York, this 23rd day of September, A. I). 1924.

THOMAS B. SLATE. I 

